Dental product

ABSTRACT

A dental product is provided packaged in a telescopically arranged multi-cavity dispensing container having at least two cylinders in an upper body thereof. Peroxide and baking soda are placed as active ingredients in separate respective semi-solid streams, each stream being in separate ones of the cylinders. Uniform dispensing of each stream to deliver relatively equivalent ribbon length of each stream by incorporating a synthetic linear anionic polycarboxylate to adjust viscosity. Preferred polycarboxylates are homopolymers of acrylic, methacrylic and maleic acids, most especially a copolymer of vinyl methyl ether and maleic acid or anhydride.

This application claims priority from a Provisional Application Ser. No.60/032,033 filed Nov. 26, 1996.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a dental product, more particularly atelescopically arranged multi-cavity dispensing container two of whichcavities are filled with semi-solid dentifrice compositions respectivelycontaining peroxide and baking soda as active ingredients.

2. The Related Art

Oral compositions with peroxide and baking soda (i.e. sodiumbicarbonate) have become commercially quite popular. The combination ofactives has been reported to promote healthy gums. When in contact,peroxide and baking soda are reactive towards one another. Thereforethese ingredients must be maintained separately until time of use.Dispensing packages have been developed which physically isolateperoxide and baking soda by separating them into different compartments.This approach has been described in a series of patents to Schaefferincluding U.S. Pat. No. 4,849,213, U.S. Pat. No. 4,528,180 and U.S. Pat.No. 4,687,663.

Dosing of flavor, fluoride and other actives has always been a challengefrom multi-compartment dispensers that simultaneously extrude more thanone stream of toothpaste. Unequal dispensing may adversely effect taste,aesthetics and oral hygiene. The most successful package for controlleddelivery has been a telescopically arranged multi-cavity dispensingpump, especially as described in U.S. Pat. No. 5,020,694 and U.S. Pat.No. 5,038,963 and U.S. Pat. No. 5,335,827 (relating to a refillcartridge), all of which are herein incorporated by reference.Commercially the pump is embodied in Mentadent Peroxide and Baking Sodatoothpaste.

Consumers have noted that even with telescoping pumps it is oftendifficult to extrude equal lengths of respective peroxide and bakingsoda dentifrice ribbons.

Accordingly, it is an object of the present invention to provide aperoxide and baking soda dental product based on a telescopicallyarranged multi-cavity dispensing container wherein essentially identicaltoothpaste ribbons from each of the cavities can be dispensed.

Another object of the present invention is to provide a peroxide andbaking soda dental product packaged in a telescopically arrangedmulti-cavity dispensing container wherein viscosity of each cavitystream can be better controlled thereby allowing more accurate dosing.

These and other objects of the present invention will become morereadily apparent from consideration of the following summary anddetailed discussion.

SUMMARY OF THE INVENTION

A dental product is provided including:

(i) a dispensing container with an upper and a lower body which aretelescopically engageable one with another, the upper body including atleast two hollow and separate cylinders, the cylinders having a firstgenerally closed end and a second end telescopically and slidinglyaccommodating at least two parallel pistons which conform to ridesealingly along the interior walls of the cylinders so as to force anyflowable materials to flow toward the first end of the cylinder uponrelative compression of the cylinders and pistons, the cylinders havingoutlet channels;

(ii) an outlet mechanism in fluid communication with the outletchannels, the outlet mechanism including adjacent outlet openingsunconnected to each other and having means for causing the flowablematerials to flow toward each other at the outlet openings to form asingle, banded, unmixed stream;

(iii) a first semi-solid flowable material containing a peroxide and asecond semi-solid flowable material containing a bicarbonate salt, eachof the first and second semi-solid materials being stored in separateones of the at least two hollow parallel cylinders, at least one of thesemi-solid materials containing from 0.05 to 20% of a synthetic anioniclinear polymeric polycarboxylate.

BRIEF DESCRIPTION OF THE DRAWING

The above features, advantages and objects of the present invention willmore fully be appreciated through the following detailed discussion,reference being made to the drawing consisting of a single FIGURE whichis an expanded view of a telescopically arranged multi-cavity dispensingpump.

DETAILED DISCUSSION

Now it has been found that in the context of telescopically arrangedmulti-cavity dispensing pumps, control of the flowable toothpastecontents can be obtained through use of synthetic anionic linearpolymeric polycarboxylates in the formulation. Polycarboxylates allowfor close matching of flow properties between a peroxide and a bakingsoda active containing stream. Flavors, fluoride and actives formulatedin either or both of the flowable streams, can therefore be dosageregulated with high accuracy. Both streams can be extruded with muchbetter control.

The dispensing container of the present invention as shown in the FIGUREincludes an upper body 2 and a lower 4, the former telescopicallyengaging within the latter. Within the lower body 4 are a pair ofparallel piston rods 6 rigidly standing, and preferably unitarily moldedwith the lower body. These rods may be hollow or solid. While thedepicted configuration is round, the rods may be rectangular or of anyother polygonal shape.

Upper body 2 includes a pair of separate parallel cylinders 8 eachhaving a first generally closed end 10 and a second end 12telescopically and slidingly accommodating piston heads 14. These headsconform to ride sealingly along interior walls of the cylinders so as toforce flowable materials to flow towards the first end of the cylinder.The cylinder walls may be formed as part of the upper body or may beformed as refill cartridges separate and removable from the upper body.Activation of flow is accomplished by hand pressure downward on the topof the upper body which pressure forces the upper body to telescopicallydescend within the lower body. Movement of the bodies causes pistons 6against each of the respective piston heads 14 to move upward alongrespective cylinders 8. Flowable material in each of the cylinders isthen forced through a pair of outlet channels 16. Flowable toothpasteexits the outlet channels passing in unmixed streams through an outletnozzle having a septum 18 maintaining respective toothpastes in unmixedrelationship to outlet openings 20.

First and second semi-solid extrudable streams of dentifrice will bestored in each of the respective cylinders 8. The first of the streamswill include a peroxide component such as an alkali metal perborate,percarbonate, urea peroxide, persilicate, perphosphate, calcium peroxideor hydrogen peroxide. Most suitable for this invention is hydrogenperoxide. Amounts of the peroxide may range from 0.01 to 15%, preferablyfrom 0.5 to 3% by weight of the first material.

The peroxide containing composition may either be a paste or gel,preferably the latter. When a gel, water will be present in amountsranging from 20 to 70%, preferably from 30 to 55%, optimally between 30to 40% by weight of the first material.

For anti-caries protection, a source of fluoride ion will normally bepresent in one or both of the flowable materials of the total oralcomposition. Fluoride sources include sodium fluoride, potassiumfluoride, calcium fluoride, stannous fluoride, stannousmonofluorophosphate and sodium monofluorophosphate. These sources shouldrelease anywhere from 25 to 3500 ppm of fluoride ion. The anti-cariesagent will be present in an amount from about 0.05 to about 3% byweight, preferably 0.2 to 0.6% by weight of the total oral composition.

Essential for the present invention are synthetic anionic linearpolymeric polycarboxylates. The synthetic anionic linear polymericpolycarboxylates operative herein are well known, being employed in theform of their partially or preferably fully neutralized water solublealkali metal (e.g. potassium or sodium) or ammonium salts. Preferred are1:4 to 4:1 copolymers of maleic anhydride or acid with anotherpolymerizable ethylenically unsaturated monomer, especially methyl vinylether(methoxyethylene) having a molecular weight (M.W.) of about 10,000to about 1,000,000. These copolymers are commercially available asGantrez AN 139 (M.W. 500,000), A.N. 119 (M.W. 250,000) and preferablyS-97 (M.W. 70,000), from ISP Corporation. The terms "synthetic" and"linear" are intended to exclude known thickening or gelling agentscomprising carboxymethylcellulose and other derivatives of cellulose andnatural gums, as well as the Carbopols which are cross-linked.

Other operative polymeric polycarboxylates include those disclosed inU.S. Pat. No. 3,956,180 herein incorporated by reference, such as the1:1 copolymers of maleic anhydride with ethyl acrylate, hydroxyethylmethacrylate, N-vinyl-2-pyrrolidone, or ethylene, the latter beingcommercially available as Monsanto EMA No. 1103 (M.W. 10,000) and EMANo. 61, and 1:1 copolymers of acrylic acid with methyl or hydroxyethylmethacrylate, methyl or ethyl acrylate, isobutyl vinyl ether orN-vinyl-2-pyrrolidone.

Additional operative polymeric polycarboxylates are disclosed in U.S.Pat. Nos. 4,138,477 and 4,183,914, herein incorporated by reference,which include copolymers of maleic anhydride with styrene, isobutyleneor ethyl vinyl ether, polyacrylic, polyitaconic and polymaleic acids,and sulfoacrylic oligomers of M.W. as low as 1,000, available asUniroyal ND-2.

Suitable generally are polymerized olefinically or ethylenicallyunsaturated carboxylic acids containing an activated carbon-to-carbonolefinic double bond and at least one carboxyl group, that is, an acidcontaining an olefinic double bond which readily functions inpolymerization because of its presence in the monomer molecule either inthe alpha-beta position with respect to a carboxyl group or as part of aterminal methylene grouping. Illustrative of such acids are acrylic,methacrylic, ethacrylic, alpha-chloroacrylic, crotonic, beta-acryloxypropionic, sorbic, alpha-chlorosorbic, cinnamic, beta-styrilactylic,muconic, itaconic, citraconic, mesaconic, glutaconic, aconitic,alpha-phenylacrylic, 2-benzyl acrylic, 2-cyclohexylacrylic, angelic,umbellic, fumaric, maleic acids and anydrides. Other different olefinicmonomers copolymerizable with such carboxylic monomers includevinylacetate, vinyl chloride, dimethyl maleate and the like. Copolymersshould contain sufficient carboxylic salt groups for water-solubility.

The synthetic anionic linear polymeric polycarboxylate component ismainly a hydrocarbon with optional halogen and O-containing substituentsand linkages as present in ester, ether and OH groups, and is generallyemployed in the instant compositions in approximate weight amounts of0.05 to 20%, preferably 0.05 to 5%, more preferably 0.1 to 2%.

Viscosity as measured on a Brookfield RVT, E Bar 2.5 RPM, for each ofthe semi-solid material streams may range from 20,000 to 1,500,000centipoise, preferably from 50,000 to 800,000 centipoise at 25° C.

A variety of other ingredients normally present in dentifrices can beselected for the semi-solid streams of peroxide and bicarbonate of thepresent invention. When the semi-solid is a gel, it is usual to employ athickening agent with the water that is a cross-linked acrylic polymer.Alternatively and most preferably gels can be structured with apolyoxyethylene-polyoxypropylene copolymer. Commercially, the copolymersare available from the BASF Corporation under the trademark PluronicF88, F99, F108 and F127. Most preferred is Pluronic F127 (more commonlydescribed by its CTFA name, Poloxamer 407) which has a molecular weightranging from 10,000 to 15,000, and containing 70% of the hydrophilicpolyoxyethylene moiety. Amounts of the copolymer can range anywhere from18-25% by weight, preferably between 19 and 24%. Poloxamers areparticularly suitable for this invention because of their wide pHtolerance, high compatibility with hydrogen peroxide and unique gelproperties.

Advantageously, glycerol should also be present in the gel component inan amount from 15 to 60%, preferably in an amount greater than 30% butless than 50%, optimally between 35 to 45% by weight of the gelcomponent.

A low pH, preferably a pH no higher than 4, optimally less than 3.3,should be maintained for the gel component. Acidification is bestaccomplished through use of a phosphorus-based inorganic or organicacid. Where Carbomer is used as a gel structurant, pH can be as high as7.5.

The second component of the oral compositions of the invention willpreferably be a bicarbonate-containing opaque paste. Elements of thiscomponent are outlined below.

Advantageously, the bicarbonate will be the salt of an alkali metal suchas sodium or potassium. Normally, the bicarbonate is included in thecomposition in an amount sufficient to provide a neutral or basic pHwhen the composition is contacted with water, preferably a pH of from7.0 to 9.5, most preferably 8.0 to 9.0. Typically, the concentrationwill range from 0.5 to 80%, preferably from 5 to 50%, optimally between8 and 20% by weight of the second semi-solid material.

A humectant and water system will normally be included. Humectants areusually polyols which, for example, may include glycerol, sorbitol,propylene glycol, lactitol, xylitol, polypropylene glycol, polyethyleneglycol, hydrogenated corn syrup and mixtures thereof. Generally theamount of humectant will range from 25 to 90%, preferably from 40 to 70%by weight of the first or second semi-solid material. Particularlypreferred is a liquid mixture of 3 to 30% water, 0 to 80% glyceroland/or 20 to 80% sorbitol.

A natural or synthetic thickening agent may be present in an amount from0.1 to 10%, preferably 0.5 to 5% by weight of the second semi-solidmaterial may be present. Thickeners may include hydroxypropylmethylcellulose, hydroxyethyl cellulose, sodium carboxymethyl cellulose,xanthan gum, tragacanth gum, karaya gum, arabic gums, Irish moss,starch, alginates and carrageenans.

Surfactants are normally also included in the semi-solid materials,especially the second component of the oral compositions of thisinvention. These surfactants may be of the anionic, nonionic, cationicor amphoteric type. Most preferred are sodium lauryl sulfate, sodiumdodecylbenzene sulfonate and sodium laurylsarcosinate. Surfactants areusually present in an amount from 0.5 to 5% by weight of a respectivesemi-solid component.

An abrasive in addition to the bicarbonate will normally be included inthe second component paste. Abrasives may be selected fromwater-insoluble alkali or alkaline earth metal salts of carbonate,aluminate and silicate. Especially preferred are silica, and alumina.Amounts of the abrasive will range from 5 to 80% by weight of arespective semi-solid component.

Sweetening agents such as saccharin, sodium cyclamate, aspartame,sucrose and the like may be included at levels from 0.1 to 5% by weightof a respective semi-solid component.

Other additives may also be incorporated into the oral compositionsincluding preservatives, silicones and anti-gingivitis actives such astriclosan and stannous gluconates.

The following examples will more fully illustrate the embodiments ofthis invention. All parts, percentages and proportions referred toherein and in the appended claims are by weight of the total compositionunless otherwise stated.

EXAMPLE 1

Typical of the present invention are paste and gel components whoseformulations are detailed under Tables I and II.

                  TABLE I    ______________________________________    Bicarbonate Paste Component    INGREDIENT            WT. %    ______________________________________     Polyol II (sorbitol and other sugars)                          48.70    Syloid 63XX (abrasive silica)                                                    15.00    Sodium Bicarbonate                                         10.00    PEG 32 (polyethylene glycol)                                                     5.00    Sylox 15x (thickening silica)                                                    4.60    Flavor                          1.00    Tetrasodium Pyrophosphate                                                        0.50    Sodium Lauryl Sulfate                                   2.98    SD Alcohol 38B                                                 2.85    Cellulose Gum                                                   0.80    Gantrez S-97                                                     0.10    Sodium Saccharin                                             4.00    Sodium Fluoride                                               0.44    Titanium Dioxide                                             0.30    Deionized Water    ______________________________________                          Balance

                  TABLE II    ______________________________________    Peroxide Gel Component    COMPONENT          WT. %    ______________________________________    Pluronic F127      20.00    Glycerin                                                   20.00    PEG-600                                                     10.00    PEG 1450                                                    10.00    Hydrogen Peroxide (35% food grade)                                      4.285    FD&C Blue                                                  0.005    Phosphoric Acid (85% w/w)                                               0.15    Deionized Water                                   Balance    ______________________________________

EXAMPLE 2

Another set of formulations suitable for the present invention are thepaste and gel components detailed under Tables III and IV.

                  TABLE III    ______________________________________    COMPONENT           WT. %    ______________________________________    Sorbitol            52.11    Syloid 63XX (abrasive silica)                                                15.00    Sodium Bicarbonate                                      15.00    PEG 32 (polyethylene glycol)                                                  5.00    Sylox 15x (thickening silica)                                                  4.00    Sodium Lauryl Sulfate                                                         2.98    SD Alcohol 38B                                              2.85    Gantrez AN-139                                             1.00    Cellulose Gum                                                0.80    Sodium Saccharin                                          0.50    Sodium Fluoride                                            0.46    Titanium Dioxide    ______________________________________                        0.30

                  TABLE IV    ______________________________________    COMPONENT          WT. %    ______________________________________    Carbopol 940 (2% solution)                       20.00    Glycerin                                                    40.00    Hydrogen Peroxide                                   4.30    FD&C Blue                                                  0.005    Sodium Hydroxide (50% soln)                                       adjusted to pH 7.0    Deionized Water                                     Balance    ______________________________________

EXAMPLE 3

This example illustrates a paste and gel combination incorporating theanionic polymer in the gel, the formulations being detailed under TablesV and VI.

                  TABLE V    ______________________________________    INGREDIENT            WT. %    ______________________________________    Polyol II (sorbitol and other sugars)                          45.25    Sodium Bicarbonate                                         20.00    Calcium Carbonate                                           15.00    PEG 32 (polyethylene glycol)                                                     5.00    Sodium Lauryl Sulfate                                   3.00    SD Alcohol 38B                                                 3.00    Sodium Monofluorophosphate                                                       1.15    Flavor                          1.00    Cellulose Gum                                                   0.80    Sodium Saccharin                                             0.50    Titanium Dioxide                                             0.30    Deionized Water    ______________________________________                          Balance

                  TABLE VI    ______________________________________    COMPONENT             WT. %    ______________________________________    Pluronic F127         25.00    Glycerin                                                        25.00    PEG 1450                                                        10.00    Hydrogen Peroxide (35% food grade)                                          4.00    Gantrez AN-116                                           1.00    FD&C Blue                                                      0.005    Phosphoric Acid (85% w/w)                                                   0.10    Deionized Water                                        Balance    ______________________________________

EXAMPLE 4

This example illustrates a paste and gel combination incorporating ananionic polymer in the paste component as detailed under Tables VII andVIII.

                  TABLE VII    ______________________________________    INGREDIENT          WT. %    ______________________________________    Sorbitol            31.32    Glycerin                                                        15.00    Syloid 63XX (abrasive silica)                                               15.00    Sodium Bicarbonate                                    15.00    PEG 32 (polyethylene glycol)                                                5.000    Sylox 15x (thickening silica)                                               4.60    Sodium Lauryl Sulfate                                                       2.50    SD Alcohol 38B                                            2.50    Gantrez S-97                                                2.00    Cellulose Gum                                              0.80    Sodium Saccharin                                        0.50    Sodium Fluoride                                          0.44    Titanium Dioxide                                        0.30    Deionized Water                                        Balance    ______________________________________

                  TABLE VIII    ______________________________________    COMPONENT             WT. %    ______________________________________    Pluronic F127         25.000    Glycerin                                                       35.000    Hydrogen Peroxide (35% food grade)                                         10.00    FD&C Blue                                                     0.005    Phosphoric Acid (85% w/w)                                                  0.10    Deionized Water                                       Balance    ______________________________________

EXAMPLE 5

A series of experiments were conducted to establish the performancebenefits of synthetic linear anionic polycarboxylates to achieve closeruniformity of extrusion between two separate dentifrice streams of adual compartment dispensing container. Base formulas for each of thesestreams are set forth under Table IX and X, respectively.

                  TABLE IX    ______________________________________    INGREDIENT           WEIGHT %    ______________________________________    Polyol II (sorbitol and other sugars)                         47.14    Syloid 63EXX                                                      15.00    Sodium Bicarbonate                                          10.00    Deionized Water                                                7.96    PEG 32 (polyethylene glycol)                                                      5.00    Sylox 15X                         6.00    Sodium Lauryl Sulphate                                                            2.98    SD Alcohol 38B                                                    2.84    Flavor                         1.30    Menthol                         0.50    Sodium Saccharin                                              0.54    Sodium Fluoride                                                0.44    Titanium Dioxide    ______________________________________                         0.30

                  TABLE X    ______________________________________    INGREDIENT      WEIGHT %    ______________________________________    Glycerin        40.00    Deionized Water                                  35.56    Hydrogen Peroxide                                                   4.285    FD&C Blue                                              0.005    Phosphoric Acid                                  0.15    Pluronic F-127                                    20.00    ______________________________________

Dispensers of the type shown in the accompanying FIGURE were separatelycharged with the formulations shown in Tables IX and X. Test 1B wasutilized as a control and further included 0.8% carboxymethyl cellulose,all other bicarbonate phases were formulated without this component.Tests 2B through 5B with the bicarbonate phases included 1.0, 0.96, 0.70and 0.40%, respectively, of Gantrez S-97. Levels of Polyol II wereadjusted for changes in the Gantrez concentration. Selection of GantrezS-97 for testing was based upon it being a typical synthetic linearanionic polycarboxylate.

Test 1P whose formula is shown under Table X served as a peroxide phasecontrol. Under Tests 2P, 3P and 4P, amounts of Gantrez S-97 wereincorporated at 1.0, 0.5 and 0.25%, respectively. Water levels wereadjusted to accommodate for changes in the Gantrez level.

Streams of dentifrice from each of the Test formulas were placed intobarrels of the dispenser shown in the FIGURE. Piston bottoms of thesedispensers were then positioned against a stationary rod and placedwithin an Instron force measurement device. Actuation force necessary toextrude formula from the cylinder was then measured on the Instronequipment. Results are listed in Table XI.

                  TABLE XI    ______________________________________                              ACTUATION FORCE    TEST NO.     % GANTREZ S-97                                IN Kg    ______________________________________    Bicarbonate Phase    1B                                           5.72    2B                                         3.59    3B                                         3.95    4B                                         4.38    5B                                         3.98    Peroxide Phase    1P                                           2.97    2P                                          5.90    3P                                          5.22    4P                                         4.45    ______________________________________

Table XI demonstrates that in the bicarbonate phase, Gantrez appears toenhance piston movement (i.e. less force necessary) as the polymerconcentration increases. Concomitantly it was observed that not onlydoes the phase flow better but an acceptable toothpaste consistency(will not leak out of pump) was still retained. Although not meant to bebound by any theory, it appears that Gantrez operates to lubricate theformula relative to the piston walls. These results were unexpected.

Likewise in the peroxide phase, incorporation of Gantrez achieved aformula that began to match in actuation force those of the bicarbonatephases. For instance, compare Test 4B with 4P. Alternatively, Gantrezneed only be placed in one of the phases. For instance, compare Test 1Bwith 2P wherein actuation forces are also essentially matched.

The foregoing description and Examples illustrate selected embodimentsof the present invention and in light thereof various modifications willbe suggested to one skilled in the art, all of which are within thespirit and purview of this invention.

What is claimed is:
 1. A dental product comprising:(i) a dispensingcontainer with an upper and a lower body which are telescopicallyengageable one with another, the upper body including at least twohollow and separate parallel cylinders, the cylinders having a firstgenerally closed end and a second end telescopically and slidinglyaccommodating at least two parallel pistons which conform to ridesealingly along the interior walls of the cylinders so as to force anyflowable materials to flow toward the first end of the cylinder uponrelative compression of the cylinders and pistons, the cylinders havingoutlet channels; (ii) an outlet means in fluid communication with theoutlet channels, the outlet means including adjacent outlet openingsunconnected to each other and having means for causing the flowablematerials to flow toward each other at the outlet openings to form asingle, banded, unmixed stream; (iii) a first semi-solid flowablematerial containing a peroxide and second semi-solid flowable materialcontaining a bicarbonate salt, each of the first and second semi-solidmaterials being stored in separate ones of the at least two hollowparallel cylinders, at least one of the semi-solid materials containingfrom 0.05 to 20% of a synthetic linear anionic polycarboxylate.
 2. Thedental product according to claim 1 wherein the polycarboxylate is acopolymer formed from monomers which in their acidic form are selectedfrom the group consisting of acrylic, methacrylic, ethacrylic, succinic,maleic acids and mixtures thereof.
 3. The dental product according toclaim 1 wherein the polycarboxylate comprises a copolymer of vinylmethyl ether and maleic acid or anhydride.
 4. The dental productaccording to claim 1 wherein the polycarboxylate is an alkali metal orammonium salt of a copolymer of vinyl methyl ether and maleic acid oranhydride having a molecular weight of about 30,000 to 500,000.
 5. Thedental product according to claim 1 wherein at least one of the twosemi-solid flowable materials further comprise a fluoride present in aneffective amount to be an anti-caries agent.
 6. The dental productaccording to claim 1 wherein the peroxide is selected from the groupconsisting of hydrogen peroxide, urea peroxide, percarbonate,perphosphate, persilicate, calcium peroxide and mixtures thereof.
 7. Thedental product according to claim 1 wherein the semi-solid materialstreams each have a viscosity ranging from 20,000 to 1,500,000centipoise at 25° C.